Absent war and revolution I'm not sure what flattens anything as quickly or as much. Taxation doesn't seem to work in a globe of transfer pricing. It's meant to. It's notable high taxing Nordic countries have less extreme disparity. Millionaires and a few billionaires no trillionaires
Note, there are many millionaires in America and India and the lowest poverty in India is far lower and more widespread than in the US but the disparity in magnitude rich to poor in India may actually be better because.. Musk and Bezos.
Not that it helps but the disparity in the USSR in cash terms was tiny by comparison but post kleptocracy that's returned to western norms. In sheer power and agency it was probably comparable. Bezos can't have millions of people sent to work camps with a single phonecall, he probably has noted the compliance costs and effort.
The 1MBD scandal shows how Asia feels about things. Suharto is gone. Marcos is gone. The Sultan of Brunei is doing fine and there's more money sloshing around Asia than ever. Jack Ma got "sat on" which suggests he'd accumulated too much power, maybe money too?
As for what the "desired" wealth distribution is, a naive view would be that everyone believes that we are all inherently of equal worth, and therefore we should all have roughly the same amount of total assets over the course of our lives, but a lot of people instead accept the premise that if there were no reward for working hard, people would freeload.
Fortunately some research has been done on what the desired amount of inequality is, and here is an article[0] which compares that desired distribution to the actual distribution, and also to the distribution that people think exists in America. The results are quite illuminating.
One way to bring the actual distribution in line with the desired distribution (other than improving democracy/representation and education) would be with an explicit annual wealth tax. For simplicity it could be designed to only apply to people with more than $5 million in net assets, and it might have to be agreed in coordination with other advanced countries (like the recent global minimum corporate tax rate agreement). The revenue could be redistributed into public services like free healthcare and college.
[0] https://www.theatlantic.com/business/archive/2012/08/america...
In general the poverty rate of the world is dropping super fast, and every year more and more of the world is raised out.
I do worry about facebook and twitter because I fear the power they're growing. But I don't care much about their balance sheets.
The small group of people that get all the wealth, get all the power. See for example how billionaires use foundations to guide government policy.
As such, I believe that in order to maintain a somewhat fair society, we might reach a point when it’s required to force billionaires to share a large part of their wealth with society, perhaps by paying debts of countries or citizens.